Users of email receive many different messages related to many different topics every day. These messages are often placed in a user's inbox with many other messages. Over time, users accumulate a large number of messages related to many different topics that are not clustered or arranged by topic. Thus, users may spend a lot of time locating email messages that are important or relevant to certain topics. Alternatively, users of email may create their own labels or folders for their messages and spend time and resources to review the messages and assign appropriate labels or folders. As the foregoing illustrates, a technique to automatically cluster messages may be desirable.